As the fracking boom matures, the drilling industry’s use of water and other fluids to produce oil and natural gas has grown dramatically in the past several years, outstripping the growth of the fossil fuels it produces.

A new study published Wednesday in the peer-reviewed journal Science Advances says the trend—a greater environmental toll than previously described—results from recent changes in drilling practices as drillers compete to make new wells more productive. For example, well operators have increased the length of the horizontal portion of wells drilled through shale rock where rich reserves of oil and gas are locked up.

They also have significantly increased the amount of water, sand and other materials they pump into the wells to hydraulically fracture the rock and thus release more hydrocarbons trapped within the shale.

The amount of water used per well in fracking jumped by as much as 770…